A 62-year-old man presents to the emergency department with a 1-week history of left lower quadrant abdominal pain. He complains of increased pain, nausea, and fever. He has had one prior episodes of similar left lower quadrant pain that resolved with antibiotic treatment alone. He has no cardiac or pulmonary risk factors. On examination, his blood pressure is 140/80 mm Hg, heart rate 110 beats/min, and temperature 38.6°C (101.5°F). His abdomen is soft and mildly distended, with left lower quadrant tenderness to palpation. He does not have evidence of generalized peritonitis. His white blood cell (WBC) count is 20,000/mm3.
What is the most likely diagnosis?
How would you confirm the diagnosis?
What are the complications associated with this disease process?
ANSWERS TO CASE 28: Diverticulitis
Summary: A 62-year-old man presents with signs and symptoms compatible with recurrent sigmoid diverticulitis.
• Most likely diagnosis: Acute sigmoid diverticulitis with an abscess.
• Confirmation of diagnosis: A CT imaging demonstrating sigmoid diverticula, colonic wall thickening, and mesenteric fat stranding.
• Associated complications: Perforation, abscess formation, bowel obstruction, and development of fistulas.
1. Learn the etiology of diverticular disease and the pathophysiology of diverticulitis.
2. Learn the workup and management of diverticulitis and its complications.
This patient’s clinical history of left lower quadrant pain and fever are suggestive of acute sigmoid diverticulitis. Although he has no evidence of generalized peritonitis, his fever, leukocytosis, and tachycardia are causes for concern at this time. A CT scan in this case is very helpful in assessing for complications of diverticulitis, particularly an abscess. Small mesenteric abscesses (<1-2 cm) associated with diverticulitis usually resolve with antibiotic therapy alone, whereas larger abscesses may require CT-guided drainage in addition to antibiotic therapy, and multiple abscesses and abscesses in inaccessible locations may require operative drainage. If the patient fails to improve clinically after 72 hours with nonoperative treatment, surgical intervention is usually warranted. Once this bout of diverticulitis is resolved with nonoperative management, a discussion regarding long-term care should be carried out with the patient. In generally, nonoperative treatment has become more widely applied for the treatment of patients with recurrent uncomplicated diverticulitis. In the past, patients with a second bout of diverticulitis and young patients below the age of 40 were recommended to undergo elective colon resections. Given the advances in antimicrobial therapy and supportive care, the recent clinical observations suggest that most uncomplicated recurrent diverticulitis patients can be safely and cost-effectively managed with nonoperative management for four bouts of attacks.
APPROACH TO: Diverticulitis
DIVERTICULOSIS: Outpouchings of the colon that do not contain all layers of the colon wall, most commonly in the sigmoid colon in Western societies. Right-sided or cecal diverticulosis tends to occur in Asian populations.
DIVERTICULITIS: Inflammation of a diverticulum caused by obstruction of the neck of the diverticulum often associated with microperforation contained with the mesocolon.
HINCHEY CLASSIFICATION OF DIVERTICULITIS:
The clinical diagnosis of diverticulitis often can be made on the basis of history and a physical examination. However, when the diagnosis is uncertain, there are signs of systemic toxicity, or there is a lack of improvement, further diagnostic studies are indicated. An abdominal CT scan is the radiologic examination of choice. A barium enema is generally deferred because of concerns for intraperitoneal leakage of barium, and colonoscopy should be used with caution because the risk of procedure-related complications is increased in this setting. However, after the acute episode is resolved, these tests can be used to document the presence of diverticulosis or fistulas and to assess for other pathologic conditions such as malignancies.
Patients can be successfully managed nonoperatively, with more than 80% of the patients expected to remain free of recurrences. Mild cases of diverticulitis can be treated on an outpatient basis. Patients with signs of systemic toxicity (fever, tachycardia, and peritonitis) should be hospitalized for hydration, treatment with intravenous antibiotics, bowel rest, and close observation. After the clinical resolution of acute diverticulitis, patients with their first, second, or third episodes and who are not immunocompromised may not require treatment other than dietary and lifestyle modifications. However, patients who are immunocompromised tend be unresponsive to medical treatment alone and usually require surgical intervention. Patients who have had four or more episodes of diverticulitis or have significantly compromised quality of life due to diverticulitis should be advised to undergo elective resection.
Complicated diverticulitis (Hinchey II, III, and IV) typically requires immediate surgical management or percutaneous drainage of abscesses. Perforated diverticulitis with generalized peritonitis should be treated with surgical exploration. If the patient is hemodynamically unstable or fecal peritonitis is present, surgical resection, colostomy, and closure of the rectal stump (Hartmann procedure) are recommended. Reanastomosis should then be performed at a later date. In the absence of significant contamination, primary anastomosis can be performed with or without proximal diversion.
Perforation that results in localized fluid collection or a diverticular abscess can be initially managed with nonoperative therapy in the absence of peritoneal signs or systemic toxicity. Mesenteric abscesses typically are treated with antibiotic therapy, and pelvic abscesses can be initially managed with percutaneous drainage. An elective one-stage procedure should then be performed at a later date. Intestinal obstruction can occur either at the time that acute diverticulitis occurs secondary to inflammation or at a later date due to a stricture. If the patient has a partial bowel obstruction, resection with anastomosis may be feasible after bowel preparation. However, patients with complete bowel obstruction should undergo urgent surgical intervention.
Diverticular fistulas can occur between the sigmoid colon and the bladder, vagina, skin, or another segment of bowel. A barium enema, a CT scan, and sigmoidoscopy can be used to visualize a fistula. Cystoscopy or a vaginal speculum examination may help identify a colovesical or a colovaginal fistula, respectively. Treatment consists of resection of the sigmoid colon, excision of the fistulous tract, and repair or resection of the other involved organ. See Figures 28–1 and 28–2 for management schemes.
Figure 28–1. Algorithm for the management of uncomplicated diverticulitis.
Figure 28–2. Algorithm for the management of complicated diverticulitis—early complications.
28.1 A 57-year-old man presents to his primary care physician with left-sided abdominal pain of 5 days’ duration, nausea, vomiting, and diarrhea. He is unable to maintain his oral intake at home. On presentation, he has mild tenderness to palpation in the left lower quadrant without peritoneal signs. His WBC count is 14,000/mm3. He has never had a similar episode in the past. What is the appropriate treatment for this patient?
A. Hospitalize for bowel rest, administration of intravenous fluids and antibiotics, and close observation.
B. Prescribe a course of outpatient antibiotics with appropriate follow-up.
C. Obtain an emergent barium enema to diagnose diverticulitis.
D. Consult the surgery department regarding future elective sigmoid resection.
E. Immediate operative treatment consisting of sigmoid resection and colostomy formation.
28.2 A 61-year-old woman presents to the emergency department with left-sided abdominal pain of 10 days’ duration. She has had constipation and states that her last bowel movement was 2 days ago. She also complains of fever to 38.9°C (102°F) and nausea and vomiting. On examination, she is diffusely tender to palpation. Plain films demonstrate dilated loops of small bowel and a paucity of gas in the rectum. Her WBC count is 26,000/mm3. What is the appropriate next step in the treatment of this patient?
A. Barium enema to confirm the diagnosis of diverticulitis.
B. Urgent sigmoidoscopy to evaluate for diverticulitis versus colonic neoplasm.
C. Obtain a CT scan of the abdomen and pelvis.
D. Admission for nasogastric decompression and administration of intravenous antibiotics.
E. Urgent surgical exploration.
28.3 A 59-year-old woman presents to her primary care physician with complaints of pneumaturia or air in the urine and recurrent urinary tract infections. She has a prior history of diverticulitis occurring 6 months ago. Which of the following tests would most likely lead to the diagnosis?
A. Order a CT scan of the abdomen and pelvis.
C. Intravenous pyelogram (IVP).
28.4 Which of the following is the most common cause of gastrointestinal tract fistulas?
A. Peptic ulcer disease
B. Inadvertent enterotomy
C. Crohn disease
D. Ulcerative colitis
28.5 For which of the following patients is sigmoid colectomy an appropriate treatment option?
A. 30-year-old man who developed two bouts of sigmoid diverticulitis that resolved with antibiotics therapy.
B. A 55-year-old man with a bout of sigmoid diverticulitis that resolved with antibiotics. His follow-up colonoscopy confirmed diverticuli in the colon. The patient is significantly concerned that he has occult colon cancer because his brother died of colon cancer recently.
C. A 57-year-old man with three bouts of diverticulitis that have resolved with antibiotics; however, he has now developed pain and distension associated with narrowing of the lumen in the sigmoid colon.
D. A 66-year-old woman with five prior episodes of diverticulitis managed successfully with bowel rest and antibiotics.
E. A 60-year-old otherwise healthy man who is hospitalized for a bout of diverticulitis with pelvic abscess that resolved with CT-guided drainage and antibiotics.
28.1 A. The patient clinically has diverticulitis and is unable to maintain oral hydration. He should be admitted to the hospital. Surgery is not indicated at this point for a patient his age with his first episode of uncomplicated diverticulitis. In addition, there is no indication for an urgent colectomy and colostomy formation at this time.
28.2 E. The patient clinically has evidence of a complete bowel obstruction, and the diffuse tenderness and leukocytosis are worrisome for a more generalized process that would not be amendable to nonoperative treatment. Surgical exploration is therefore warranted. A barium enema and colonoscopy are contraindicated in this situation.
28.3 D. The CT scan can be used to confirm the diagnosis of a colovesical fistula and to localize the fistulous tract. Urinalysis will be unhelpful, because there will be bacteria in the bladder. The IVP visualizes the upper portion of the urinary tract (kidneys and ureters) and will not likely be helpful because there is no ureteral injury. The communication between the colon and bladder is often so small in this setting, a negative cystography will not sufficiently eliminate the possibility of a colovesicular fistula.
28.4 E. The most common cause of gastrointestinal tract fistulas is diverticulitis, usually causing a colovesical (colon-to-bladder) fistula. Air or stool in the urine or frequent urinary tract infections are typical presenting findings.
28.5 D. Risk-benefit analysis has demonstrated that surgery benefits outweigh the risks when colectomy is performed after the fourth bout of diverticulitis; however, any decision for surgery also must take into account the patient’s life expectancy and overall fitness to undergo operative intervention. Young age is no longer considered an indication for colectomy in diverticulitis treatment. Follow-up of patients with uncomplicated diverticulitis suggests that only 13% of patients would ultimately require surgery; therefore medical treatment is highly successful in these patients. Hospitalization for diverticulitis-related complications does not adversely influence the natural history of diverticulitis, therefore does not mandate surgical treatment.
CT imaging is often helpful in identifying and guiding percutaneous drainage of abscesses related to diverticulitis.
Diverticulitis is the most common cause of gastrointestinal tract fistulas.
Observations suggest that only 10% to 15% of patients with one to two bouts of acute diverticulitis go on to require surgery.
Surgical intervention for uncomplicated diverticulitis is safe and cost-effective when applied for patients with four or more episodes of uncomplicated diverticulitis.
Complicated diverticulitis such as perforation or fistula is usually treated surgically or with percutaneous interventions.
Bordeianou L, Hodin R. Controversies in the surgical management of sigmoid diverticulitis. J Gastrointest Surg. 2007:542-548.
Peppas G, Bliziotis IA, Oikonomaki D, Falagas ME. Outcomes after medical and surgical treatment of diverticulitis: a systemic review of the available evidence. J Gastroenterol Hepatol. 2007;22:1360-1368.
Stocchi L Current indications and role of surgery in the management of sigmoid diverticulitis. World J Gastroenterol. 2010;16:804-817.